3.5. Sample Preparation

Five milliliters of DMSO were transferred to a glass vial for headspace injection containing 1 g losartan potassium. The sample was then gently vortexed using a vortex mixer at the maximum rotation speed for 5 min. The clear sample solution was placed into the HS-20 headspace autosampler. The sample was incubated in the headspace oven at 150 °C under the vibration level of 5, with the appropriate sample equilibrating time of 15 min. The residual nitrosamines were then vaporized into the vial headspace and directly injected into the column.